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21.
New azo-derivatives of gossypol and its imines were described. Their physicochemical properties and data on their interferon-inducing activity were presented.  相似文献   
22.
It has been found by the ESR technique that the adsorption of propylene on zinc oxide leads to the formation of a -allyl radical. It is suggested that the radical species of the surface allyl compound on this catalyst is responsible for its high selectivity in the dehydroaromatization of propylene to benzene.
, - . , .
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23.
    
Summary A new phenolic compound — gossyvertin — has been isolated from the stems of a cotton plant infected with fungusVerticillium dahliae Kleb.; the structure 8-formyl-1,7-dihydroxy-5-isopropyl-2-methoxy-3-methylnaphthalene has been proposed for gossyvertin.Division of Bioorganic Chemistry, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 238–242, March–April, 1976.  相似文献   
24.
A glucomannan has been isolated from the tubers ofArum korolkovii Regel. It has been shown that the polysaccharide contains O-acetyl groups and consists mainly of (1 → 4)-β-linked aldohexopyranose units of glucose and mannose in a ratio of 1:1.6. The nonreducing ends of the glucomannan are glucose residues, and branching is localized at C2 and C3 of mannose.  相似文献   
25.
Conclusions Two anthocyanin glycosides have been isolated from the flowers ofHibiscus cannabinus var. simplex. One of them is a new glycoside, which has been called cannabinin, and the second is the known glycoside myrtillin, this being the first time that it has been isolated from the flowers of Kenaf hemp.Scientific-Research Institute for the Chemistry and Technology of Cotton Cellulose, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 723–727, November–December, 1971.  相似文献   
26.
Tests have been made to benchmark and assess the relative accuracies of low-order multireference perturbation theories as compared to coupled cluster (CC) and full configuration interaction (FCI) methods. Test calculations include the ground and some excited states of the Be, H(2), BeH(2), CH(2), and SiH(2) systems. Comparisons with FCI and CC calculations show that in most cases the effective valence shell Hamiltonian (H(v)) method is more accurate than other low-order multireference perturbation theories, although none of the perturbative methods is as accurate as the CC approximations. We also briefly discuss some of the basic differences among the multireference perturbation theories considered in this work.  相似文献   
27.
A new compound, which we have called gossindan, has been isolated from the products of the oxidation of gossypol by oxygen in an alkaline medium. The structure of gossindan has been established on the basis of a study of IR, mass, PMR, and13C NMR spectra and x-ray structural analysis as 6,6-di-(2,7-dihydroxy-3-isopropyl-5-methylindan-1-one).A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, Fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–58, January–February, 1994.  相似文献   
28.
This review gives information on the distribution of flavonoids (flavonol and anthocyanin glycosides, catechins, and proanthocyanidins in plants of the family Malvaceae, namely the various species of the genera Gossypium, Hibiscus, Altheae, etc. It is shown that the flavonols are represented by glycosides of kaempferol, quercetin, myricetin, herbacetin. gossypetin, and hibiscetin, the most widespread being glycosides of quercetin and kaempferol. Characteristic for the majority of representatives of the families that were studied are flavonols having a hydroxy group in the C-8 position. Anthocyanins are represented by glycosides of cyanidin and of delphinidin. However, together with these, glycosides of methoxylated anthocyanins have also been detected — peonidin, petinidin, and malvidin. Sources of a food dye have been revealed among representatives of the family. Literature sources up to 1991 have been included.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 3–19, January–February, 1994.  相似文献   
29.
Transformations of 1,1,6,6,7,7-hexahydroxy-3,3-dimethyl-5,5-diisopropyl-2,2-dinaphthylidene-8,8-dibarbituric acid (batridene) in DMSO are studied.  相似文献   
30.
Emergence of the multidrug-resistant pathogens has rendered the current therapies ineffective thereby, resulting in the need for new drugs and drug targets. The accumulating protein sequence data has initiated a drift from classical drug discovery protocols to structure-based drug designing. In the present study, in silico subtractive genomics approach was implemented to find a set of potential drug targets present in an opportunist bacterial pathogen, Acinetobacter baumannii (A. baumannii). Out of the 43 targets identified, further studies for protein model building and lead-inhibitor identification were carried out on two cell-essential targets, MurA and MurB enzymes (of A. baumannii designated as MurAAb and MurBAb) involved in the peptidoglycan biosynthesis pathway of bacteria. The homology model built for each of them was further refined and validated using various available programs like PROCHECK, Errat, ProSA energy plots, etc. Compounds showing activity against MurA and MurB enzymes of other organisms were collected from the literature and were docked into the active site of MurAAb and MurBAb enzymes. Three inhibitors namely, T6361, carbidopa, and aesculin, showed maximum Glide score, hydrogen bonding interactions with the key amino acid residues of both the enzymes and acceptable ADME properties. Furthermore, molecular dynamics simulation studies on MurAAb–T6361 and MurBAb–T6361 complexes suggested that the ligand has a high binding affinity with both the enzymes and the hydrogen bonding with the key residues were stable in the dynamic condition also. Therefore, these ligands have been propsed as dual inhibitors and promising lead compounds for the drug design against MurAAb and MurBAb enzymes.  相似文献   
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